Polymer melt composite vibration injection molding device

Abstract

The present invention discloses a polymer melt composite vibration injection molding device, including an injection molding machine, a composite vibration system, and an injection mold, wherein the biggest difference from ordinary injection molding lies in the composite vibration system of the device. The composite vibration system includes a medium- and low-frequency hydraulic vibration system and a high-frequency ultrasonic vibration system. The hydraulic vibration is composed of a hydraulic pump, a rotary valve, a hydraulic cylinder, and a vibration rod. The vibration rod extends into the polymer melt flow channel, and the number is even. It can be divided into two groups and reciprocates in the same direction or in the opposite direction to achieve pressure vibration or shear vibration of the melt. The ultrasonic vibration system is composed of an ultrasonic generator, a transducer, a horn and a vibration rod. The ultrasonic vibration rod extends into the polymer melt flow channel and directly acts on the melt. The device can significantly reduce the melt viscosity and is suitable for thin-walled or large injection molded parts that are difficult to fill, as well as injection molded parts with many weld marks or poor weld mark strength.

Description

Technical Field

[0001] The invention relates to the field of polymer processing equipment, in particular to a polymer melt composite vibration injection molding device which can improve polymer mold filling performance and reduce welding marks. Background Art

[0002] The existing mainstream polymer melt injection molding device can only provide a simple shear field, and the shear direction, shear rate, etc. are unchanged. This simple shear field can cause the slippage of the molecular chains between the upstream layers perpendicular to the flow direction, so that the entanglement points are released to a certain extent, causing the viscosity to decrease, which is called "shear thinning". Although the viscosity decrease caused by shear thinning is beneficial to the processing process, due to the constant shear rate and short shear time, when the recovery entanglement caused by the thermal motion of the molecular chain and the shear-induced disentanglement reach a dynamic balance, the entanglement state of the molecular chain will remain unchanged, the disentanglement will not continue, and the viscosity will remain unchanged.

[0003] The Chinese invention with the publication number CN112793098A discloses an injection molding machine that can improve the fluidity of polymer materials. It specifically discloses that by setting a plurality of parallel and raised blocks on the outer surface of the core shaft of the disentanglement mechanism of the injection molding machine, a good mixing effect can be produced during material transportation, which can increase the uniformity of the shearing effect on the plastic melt, thereby avoiding the disadvantage of poor disentanglement effect caused by uneven shearing in the layer thickness direction; at the same time, the space between the blocks is large, which can effectively increase the capacity of the melt and improve the disentanglement efficiency. The main problems are: 1. Its disentanglement method is relatively single, mainly relying on the shearing method, and the disentanglement effect is limited; 2. The direction in which the polymer melt enters the device is different from the direction of the injection molding device, and an additional power device (drive motor) is required to make the polymer melt flow in the specified direction for injection molding.

[0004] The Chinese invention patent with the publication number CN110815628A discloses a polymer melt disentanglement device, which specifically discloses a method of applying a circumferential rotation stress field or a circumferential vibration stress field or a composite motion stress field of circumferential rotation and circumferential vibration to the melt, so that the molecular chains in the melt are gradually moved away when the force direction is continuously changed by tension and relaxation under the circumferential shear field or circumferential vibration field, especially under the composite stress field of circumferential shear and circumferential vibration superposition, thereby achieving a high degree of disentanglement. The problems it has are as follows: 1. Its disentanglement method is relatively single, mainly relying on mechanical methods (vibration + shearing), and the disentanglement effect is limited; 2. The direction in which the polymer melt enters the device is different from that of the injection molding device, and an additional power device (drive motor) is required to make the polymer melt flow in the specified direction for injection molding.

[0005] The Chinese invention patent with publication number CN114633448A discloses a testing machine with integrated functions of wide-band vibration test / rheological measurement, which specifically discloses that high-amplitude and low-frequency mechanical vibration and high-frequency and low-amplitude ultrasonic vibration are used together to form a wide-band vibration field to improve the processing efficiency and mechanical properties of polymers. However, it has the following technical problems:

[0006] 1. In fact, it is difficult for technicians in this field to directly apply the test instrument to industrial production, and its structure is complex, and the cost and requirements for manufacturing, installation and use are high;

[0007] 2. Its feed port, material flow channel and discharge port are perpendicular to each other, and the flow direction of the polymer needs to pass through two 90-degree right angles. Obviously, these right angles will inevitably lead to a slower flow rate and lower temperature of the polymer melt here. However, since it is a test instrument, as long as it produces material at the discharge port, even if the material fluidity becomes worse or the temperature is lower, it will not affect the measurement of its performance in subsequent experiments. If it is used in industrial production, it will be a big problem;

[0008] 3. Its mechanical vibration direction reciprocates along the flow direction of the polymer melt, which is equivalent to applying a single-direction shear flow field in the melt flow direction. The melt is sheared by friction with the upper and lower mold walls, which is consistent with the shear field principle in the conventional injection molding process, except that the melt is pushed back and forth on both sides. This shear field is difficult to achieve effective disentanglement. In the perpendicular direction to the flow, due to the speed difference between layers, the macromolecules will slip relatively, so that the cohesive entanglement points and topological entanglement points are both released to a certain extent, causing the viscosity to decrease. This disentanglement is inevitable in the processing process, but the disentanglement effect is general, and it cannot achieve deep disentanglement and efficient disentanglement.

[0009] 4. Discontinuous discharge is not a problem in experimental applications, but it is discontinuous production in industry, which is obviously unacceptable. The specification mentions that "connecting multiple test machines in parallel, combining and matching the time of discharging materials from the outlets of each test machine can ensure the continuous supply of polymer melt", but connecting multiple test machines in parallel will inevitably increase the system complexity and system assembly cost by multiples, and the problem of coordinating the test machines to achieve continuous feeding is also a challenge for technicians in this field, which is difficult to achieve in industrial production. Summary of the invention

[0010] In response to the above technical problems, the present application provides a polymer melt injection molding device with hydraulic vibration + ultrasonic vibration, which has a simple structure and is suitable for industrial production applications.

[0011] In order to achieve the above invention objectives, this application provides the following technical solutions:

[0012] A polymer melt composite vibration injection molding device, comprising an injection molding machine, a composite vibration device, and an injection mold;

[0013] The injection molding machine is used to plasticize the polymer, and the plasticized polymer melt flows through the composite vibration device and then enters the injection mold; the injection mold is used to shape the polymer melt;

[0014] The composite vibration device comprises a feeding die, a hydraulic vibration module and an ultrasonic module;

[0015] The transfer die is composed of an upper die and a lower die. The transfer die parting surface is provided with a flow channel that runs through both ends of the transfer die and allows the polymer melt to flow. The upper die is provided with at least two first through holes, and the lower die is provided with at least one second through hole. The first through hole and the second through hole are respectively perpendicular to the flow channel and connected.

[0016] The hydraulic vibration module comprises a vibration rod and a hydraulic cylinder; the vibration rod is installed in the first through hole and extends into the flow channel, and the end of the vibration rod away from the upper mold is connected to the hydraulic cylinder, and the hydraulic cylinder is used to drive the vibration rod to perform piston movement in the first through hole;

[0017] The ultrasonic module comprises an ultrasonic vibration head and a horn; the ultrasonic vibration head is arranged at one end of the horn; the horn is installed in the second through hole and the ultrasonic vibration head extends into the flow channel.

[0018] The two ends of the flow channel are respectively connected to the injection molding machine and the injection mold.

[0019] In some preferred embodiments, the parting surfaces of the upper mold and the lower mold are stepped to facilitate positioning.

[0020] In some preferred embodiments, a convergent boss is further provided at a position of the flow channel surface facing the second through hole, for reducing the thickness of the flow channel at this location; the cross-sectional shape of the flow channel is rectangular, and its width is not less than the diameter of any of the first through hole and the second through hole.

[0021] In some preferred embodiments, a wear-resistant sleeve is disposed in the first through hole, the inner surface of the wear-resistant sleeve has a clearance fit with the vibration rod, and the outer surface of the wear-resistant sleeve has an interference fit with the first through hole; and a flexible sleeve is disposed in the second through hole.

[0022] In some preferred embodiments, the hydraulic cylinder includes a horizontal slide groove; the vibration rod is connected to the horizontal slide groove via a slider disposed at one end away from the mold.

[0023] In some preferred embodiments, a plurality of third through holes are provided on a side of the horizontal slide groove away from the left groove, and threaded blind holes are provided at positions of the sliding block corresponding to the third through holes.

[0024] In some preferred embodiments, the hydraulic cylinder further includes a piston rod; the movable end of the piston rod is connected to the horizontal slide groove.

[0025] Beneficial Effects

[0026] 1. The polymer melt flow channel is reasonably designed, and the injection molding machine can be connected at the flow channel feed end and the injection mold can be connected at the discharge end to realize the industrialized polymer melt injection molding production application;

[0027] 2. The disentanglement effect is achieved through the composite external force field of superimposed ultrasonic vibration and hydraulic vibration, which can greatly reduce the viscosity of the polymer melt. The device has three modes: ultrasonic vibration mode, hydraulic vibration mode and hydraulic-ultrasonic composite vibration mode. Ultrasonic vibration has a better effect on reducing the viscosity of temperature-sensitive polymers, and hydraulic vibration has a better effect on shear-sensitive polymers. Composite vibration can achieve the superposition or synergistic effect of the two. The reduction in viscosity can greatly reduce the injection pressure while ensuring the filling effect, reduce the difficulty of injection molding, shorten the cooling time, and achieve low-energy and efficient injection molding of high-viscosity and difficult-to-process polymers; the injection molding temperature can be greatly reduced while keeping the melt viscosity roughly unchanged. Low-temperature molding can reduce degradation during the molding process, reduce the overall temperature difference of the product, and reduce internal stress; it can effectively solve the defects such as warping, insufficiency of filling, and weld marks caused by insufficient melt fluidity in the molding process of thin-walled and large-sized injection molded parts, and improve product quality;

[0028] 3. After chain disentanglement, the macromolecules have higher mobility, the ordering process of the system is accelerated, and the crystallization ability of the polymer is enhanced, making the "structural" process of the polymer melt crystal morphology easier to control and adjust, so that under the induction of external fields or nucleating agents, special crystal structures such as string crystal structures and columnar crystal structures can be generated, which can improve the degree of crystallization perfection and produce oriented structures, thereby significantly improving the physical and mechanical properties of the products. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the overall structure of a device in a preferred embodiment of the present invention;

[0030] Figure 2 It is a schematic diagram of the overall structure of another preferred embodiment of the device in the present invention;

[0031] Figure 3 This is a schematic diagram of the shaft side structure of a composite vibration device in a preferred embodiment of the present invention;

[0032] Figure 4 It is a front view structural schematic diagram of a composite vibration device in a preferred embodiment of the present invention;

[0033] Figure 5It is a schematic diagram of the side structure of a composite vibration device in a preferred embodiment of the present invention;

[0034] Figure 6 It is an enlarged schematic diagram of the main structure of the AA section in a preferred embodiment of the present invention;

[0035] Figure 7 It is a structural schematic diagram of the AA cross-section feed mold installed with the injection molding machine connecting flange and the nozzle in a preferred embodiment of the present invention;

[0036] Figure 8 It is an enlarged schematic diagram of the AA cross-section structure of the feeding die in a preferred embodiment of the present invention;

[0037] Fig. 9 It is an enlarged schematic diagram of the BB cross-section structure of the material transfer die in a preferred embodiment of the present invention;

[0038] Fig.10 This is a schematic diagram of the processing performance results of LDPE in a preferred experimental example of the present invention;

[0039] Fig.11 This is a schematic diagram of the PLA processing performance results in a preferred experimental example of the present invention;

[0040] In the figure: 1. injection molding machine; 2. composite vibration device; 3. injection molding mold; 4. injection molding machine connecting flange; 5. nozzle; 21. feeding mold; 22. hydraulic vibration module; 23. ultrasonic module; 210. convergent boss; 211. upper mold; 212. lower mold; 213. feeding end; 214. discharging end; 215. flow channel; 216. first through hole; 217. second through hole; 218. wear-resistant sleeve; 219. flexible sleeve; 221. vibration rod; 222. hydraulic cylinder; 231. amplitude rod; 232. ultrasonic vibration head; 2221. horizontal slide; 2222. piston rod; 2223. threaded blind hole; 2224. third through hole; DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of the present invention clearer, the present invention is further described below in conjunction with the accompanying drawings. In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention.

[0042] This embodiment discloses a polymer melt composite vibration injection molding device, such as Figure 1-Figure 9As shown, it includes an injection molding machine 1, a composite vibration device 2, an injection mold 3, an injection molding machine connecting flange 4 and a nozzle 5;

[0043] The injection molding machine 1 is used to plasticize the polymer material. The plasticized polymer melt flows through the composite vibration device 2 and then enters the injection mold 3. The plasticized polymer melt flows through the composite vibration device 2 and then enters the injection mold 3. The injection mold 3 is used to shape the polymer melt.

[0044] like Figure 1 As shown, an example of directly connecting the injection molding machine 1 with the composite vibration device 2 and then connecting the composite vibration device 2 to the injection mold 3 after the discharge nozzle is connected, in other preferred embodiments, such as Figure 2 As shown, the injection molding machine 1 may be connected to the nozzle first and then connected to the composite vibration device 2 and the injection mold 3 in sequence. The specific use of the above two embodiments may be determined by those skilled in the art according to the actual needs of the site. It should be understood that since the injection molding machine 1 and the injection mold 3 are not the focus of this application, a simplified drawing method is used in the figure, and no further limitation is made in the text description. Those skilled in the art may adopt the structural settings commonly used in the prior art.

[0045] The composite vibration device 2 includes a feeding die 21, a hydraulic vibration module 22 and an ultrasonic module 23;

[0046] The transfer mold 21 is composed of an upper mold 211 and a lower mold 212. The parting surface of the transfer mold 21 is provided with a flow channel 215 that runs through both ends of the transfer mold 21 for the polymer melt to flow; the upper mold 211 is provided with at least two first through holes 216, and the lower mold 212 is provided with at least one second through hole 217; the first through hole 216 and the second through hole 217 are respectively perpendicular to and connected with the flow channel 215; in some preferred embodiments, in order to enable more precise positioning of the upper and lower molds 212 when they are closed, and to allow the greater pressure during the injection molding process to cause the material to overflow the flow channel 215 and enter the parting surface, causing leakage, the parting surfaces of the upper mold 211 and the lower mold 212 are stepped to facilitate positioning, for example, matching grooves and bosses are provided to solve the above problems. The cross-sectional size of the flow channel 215 is generally small. In order to make the vibration module and the ultrasonic module 23 more fully contact the polymer melt in the flow channel 215, it is considered to design the cross-sectional shape of the flow channel 215 to be rectangular, and its width is not less than the diameter of any one of the first through hole 216 and the second through hole 217.

[0047] The hydraulic vibration module 22 includes a vibration rod 221 and a hydraulic cylinder 222; the vibration rod 221 is installed in the first through hole 216 and extends into the flow channel 215, and the end of the vibration rod 221 away from the upper mold 211 is connected to the hydraulic cylinder 222, and the hydraulic cylinder 222 is used to drive the vibration rod 221 to perform piston movement in the first through hole 216; it should be understood that there are many ways to drive the vibration rod 221, and various driving methods such as mechanical drive, electric drive, and hydraulic drive can be used. In this application, according to the different driving forms adopted, the vibration frequency of the vibration rod 221 is 0-200Hz, and the vibration amplitude is 0-140mm. In actual selection, in order to ensure sufficient amplitude, it generally does not exceed 10Hz.

[0048] The ultrasonic module 23 includes an ultrasonic vibration head 232 and a horn 231; the ultrasonic vibration head 232 is arranged at one end of the horn 231; the horn 231 is installed in the second through hole 217 and the ultrasonic vibration head 232 extends into the flow channel 215. It should be understood that the ultrasonic vibration module is a commonly used device in the field. In addition to the ultrasonic vibration head 232 and the horn 231, it also includes necessary components such as an ultrasonic transmitter, a transducer, a cooling device, an ultrasonic generator and an electric parameter meter. Therefore, this application no longer describes structures and components that are not directly related to this technical solution. Since in this application, the ultrasonic vibration head 232 is inserted into the lower mold 212 from bottom to top, therefore, a suitable position on the outer surface of the horn 231 should also be provided with a connection device for connecting and fixing. In some preferred embodiments, it can be a connecting flange; when the horn 231 is inserted into place, the horn 231 is connected and fixed to the lower mold 212 through the connecting flange. In some other preferred embodiments, considering that the mold is generally a metal mold and ultrasonic waves are not suitable for directly acting on metal surfaces, a flexible sleeve 219 is provided in the second through hole 217, and the inner surface of the flexible sleeve 219 is interference fit with the ultrasonic vibration head 232, and the outer surface is transition fit with the second through hole 217. Preferably, the flexible sleeve 219 is high temperature rubber.

[0049] In some preferred embodiments, the two ends of the flow channel 215 can be connected to the injection molding machine connection flange 4 and the nozzle 5, respectively. It should be understood that the injection molding machine connection flange 4 and the nozzle 5 are not necessary components, and are only limited as a preferred implementation in this embodiment, and the injection molding machine connection flange 4 and the nozzle 5 are both detachably connected to the feed mold 21, preferably flange connection. The injection molding machine connection flange 4 is used to connect the mold and the injection molding machine, and the injection molding machine can be any one of the commonly used injection molding machines in the field, and in order to realize industrial injection molding production, other necessary equipment such as injection system, mold clamping system, heating system, cooling system, control system, etc., are equipped by those skilled in the art as needed, because it is not the focus of the present invention, so it will not be repeated.

[0050] In order to improve the effect of the ultrasonic vibration head 232 on the polymer melt in the flow channel 215 and increase the penetration of ultrasonic waves, some preferred embodiments also consider providing a convergent boss 210 on the surface of the flow channel 215 opposite to the second through hole 217, so as to reduce the thickness of the flow channel 215 at this location, thereby achieving the following effects: 1. It helps to establish a higher pressure on both sides of the convergent boss 210 in the flow channel 215, so that the vibration module can better shear and stretch the polymer melt; 2. It reduces the thickness of the polymer melt at this location, so that it can better accept the high-frequency vibration force field of ultrasonic waves, so that ultrasonic waves can play a better penetration role, thereby achieving a better disentanglement effect.

[0051] It should be noted that from the perspective of melt disentanglement, in a simple shear force field generated by a single mechanical vibration, the cohesive entanglements perpendicular to the shear direction are pulled apart, while the cohesive entanglement points parallel to the shear direction are not greatly affected. When the topological entanglement point is located at one end of the molecular chain, the macromolecular chain may slip and be pulled apart in the shear force field, while when the entanglement point is in the middle of the macromolecule, it will become tighter and tighter in the pure shear force field and difficult to disengage, resulting in a limited degree of melt disentanglement.

[0052] However, in a single ultrasonic vibration field, the cavitation effect of ultrasound is reduced due to the high viscosity of the polymer melt, and its penetration ability is limited. In addition, in the absence of shear and stretching external fields, a single ultrasonic field can only relax the topological entanglement points, making it difficult to achieve relative sliding disentanglement of molecular chains from the entanglement points.

[0053] The design idea of ​​the present invention is to use ultrasound to apply ultra-high frequency impact to the melt to instantly break the condensation and entanglement in the melt, and then combine it with a high-frequency reciprocating vibration shear field. Under the action of the tension and relaxation vibration field, the shear force field can make the molecular chains gradually loosen and gradually pull apart from the opened entanglement points, thereby achieving a high degree of disentanglement.

[0054] At the same time, from the analysis of the essential characteristics of molecular chain movement, the molecular weight of the polymer chain has a certain dispersion and exhibits typical viscoelastic behavior characteristics. The response time of different molecular chains to the external field is inconsistent and is distributed within a time range (relaxation time spectrum). If the external field changes at a certain moment, some molecular chains may be able to respond in time to keep up with the pace of external field changes, but the majority of molecular chains will show varying degrees of lag and still move in the original way, resulting in differences in the movement of each molecular chain. The composite external field that combines different forms of movement can cause maximum disturbance to the melt, which is conducive to the "opening" of entangled molecular chains.

[0055] In some preferred embodiments, a specific structural example of a vibration rod 221 connected to a hydraulic cylinder 222 is provided, wherein the hydraulic cylinder 222 includes a horizontal slide groove 2221; the vibration rod 221 is connected to the horizontal slide groove 2221 via a slider disposed at one end away from the mold. During installation, the vibration rod 221 is installed by sliding one end with the slider into the horizontal slide groove 2221, and then inserting the other end into the first through hole 216. In other preferred embodiments, in order to lock the installed vibration rod 221 in position in the slide groove, a plurality of third through holes 2224 are disposed on the side of the horizontal slide groove 2221 away from the groove, and threaded blind holes 2223 are disposed at positions corresponding to the slider and the third through holes 2224. The position of the third through hole 2224 corresponds to the installation position of the vibration rod 221. When the vibration rod 221 slides into position in the slide slot, a bolt is passed through the third through hole 2224 and screwed into the threaded blind hole 2223 to lock the position of the vibration rod 221. It should be understood that in order to prevent the bolt head from being exposed on the surface of the horizontal slide slot 2221 after installation, it is considered to set the third through hole 2224 as a stepped through hole.

[0056] In some preferred embodiments, a specific example of the composition of the hydraulic cylinder 222 is also given, wherein the hydraulic cylinder 222 also includes a piston rod 2222; the movable end of the piston rod 2222 is connected to the horizontal slide 2221. The piston rod 2222 can be any common hydraulic cylinder telescopic structure, or other telescopic structures such as a pneumatic cylinder, an electric cylinder, or mechanical telescopic structures, etc., which is not further limited in the present application, and those skilled in the art can determine the specific shape of the energy supply device according to the specific shape of the piston rod 2222 in combination with conventional technology in the field. For example, when the piston rod 2222 adopts a hydraulic cylinder, the energy supply device includes hydraulic pipelines, hydraulic pumps, liquid outlet boxes, hydraulic valves, hydraulic control systems and other components. Furthermore, in order to adjust the telescopic amplitude of the piston rod 2222 and thus adjust the vibration amplitude of the vibration rod 221, an amplitude adjustment device such as an adjustment nut commonly used in the field can also be provided.

[0057] The following description is given below with regard to the working process of the present invention:

[0058] The molten compound flows out of the injection molding machine through the injection molding machine connection flange 4 and enters the flow channel 215 in the feed mold 21. The cross-sectional size of the flow channel 215 is smaller than the discharge size of the injection molding machine connection flange 4, so the molten compound converges in the flow channel 215, forming a higher pressure and tensile convergence effect. The vibration rod 221 extends into the flow channel 215 when the piston moves under the action of the hydraulic cylinder 222, directly contacts and acts on the molten compound, and directly acts on the molten compound with the vibration force, so that it is reciprocatedly compressed and released in the flow channel 215, and when the vibration rod 221 moves to the lowest end, the distance between the surface of the vibration rod 221 and the bottom surface of the flow channel 215 is small, forming a convergent flow channel 215, and strengthening the repeated tensile effect on the molten compound; with the reciprocating movement of the vibration rod 221, the molten polymer is repeatedly compressed, released, sheared and stretched. The flow channel 215 at the ultrasonic vibration head 232 is narrowed by the convergent boss 210, so that the flow channel 215 produces a convergent effect and increases the pressure of the molten compound, extending the action time of the ultrasonic wave on the molten compound. After the combined action of mechanical vibration and ultrasonic wave, the molten compound enters the nozzle 5 through the discharge end 214 and is sprayed into the injection mold to be formed into the required plastic product. The vibration action area of ​​the present application is large, with a strong vibration effect, and it can not only provide a mechanical vibration stress field and an ultrasonic high-frequency stress field of compression release separately, but also provide a synergistic effect of the two stress fields, so as to achieve effective regulation and control of the processing performance of the polymer melt and efficient disentanglement.

[0059] Experimental example

[0060] like Figure 10-11 As shown, this experimental example takes PLA (biodegradable plastic polylactic acid, polylactic acid) and LDPE (low-density polyethylene, Low Density Polyethylene) as examples to study the various properties of materials produced by the polymer melt injection molding device of the present application.

[0061] After applying the ultrasonic and vibration composite force field, the melt pressure and apparent viscosity of PLA and LDPE when entering nozzle 5 decreased significantly, indicating that the highly disentangled melt has excellent processing performance after composite external field treatment. The device can effectively increase the injection molding rate, reduce the nozzle 5 pressure and melt viscosity, and continuously and efficiently inject products with high mechanical properties.

[0062] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. Polymer melt composite vibration injection molding device, characterized in that: It comprises an injection molding machine (1), a composite vibration device (2), and an injection mold (3); The injection molding machine (1) is used to plasticize the polymer, and the plasticized polymer melt flows through the composite vibration device (2) and then enters the injection mold (3); the injection mold (3) is used to shape the polymer melt; The composite vibration device (2) comprises a feeding die (21), a hydraulic vibration module (22) and an ultrasonic module (23); The transfer mold (21) is composed of an upper mold (211) and a lower mold (212); a parting surface of the transfer mold (21) is provided with a flow channel (215) that runs through both ends of the transfer mold (21) and allows the polymer melt to flow; the upper mold (211) is provided with at least two first through holes (216), and the lower mold (212) is provided with at least one second through hole (217); the first through hole (216) and the second through hole (217) are respectively perpendicular to and connected to the flow channel (215); A convergent boss (210) is also provided at a position on the surface of the flow channel (215) facing the second through hole (217) to reduce the thickness of the flow channel (215) at this position; the cross-sectional shape of the flow channel (215) is rectangular, and its width is not less than the diameter of any one of the first through hole (216) and the second through hole (217); The hydraulic vibration module (22) comprises a vibration rod (221) and a hydraulic cylinder (222); the vibration rod (221) is installed in the first through hole (216) and extends into the flow channel (215); one end of the vibration rod (221) away from the upper mold (211) is connected to the hydraulic cylinder (222); the hydraulic cylinder (222) is used to drive the vibration rod (221) to perform piston movement in the first through hole (216); The ultrasonic module (23) comprises an ultrasonic vibration head (232) and a horn (231); the ultrasonic vibration head (232) is arranged at one end of the horn (231); the horn (231) is installed in the second through hole (217) and the ultrasonic vibration head (232) extends into the flow channel (215); The two ends of the flow channel (215) are respectively connected to the injection molding machine (1) and the injection mold (3).

2. The polymer melt composite vibration injection molding device according to claim 1, characterized in that: The parting surfaces of the upper mold (211) and the lower mold (212) are in a stepped shape for easy positioning.

3. The polymer melt composite vibration injection molding device according to claim 1, characterized in that: A wear-resistant sleeve (218) is arranged in the first through hole (216), the inner surface of the wear-resistant sleeve (218) is clearance-fitted with the vibration rod (221), and the outer surface is interference-fitted with the first through hole (216); a flexible sleeve (219) is arranged in the second through hole (217).

4. The polymer melt composite vibration injection molding device according to claim 1, characterized in that: The hydraulic cylinder (222) comprises a horizontal slide groove (2221); the vibration rod (221) is connected to the horizontal slide groove (2221) via a sliding block arranged at an end away from the mold.

5. The polymer melt composite vibration injection molding device according to claim 4, characterized in that: A plurality of third through holes (2224) are arranged on one side of the horizontal sliding groove (2221) away from the groove, and threaded blind holes (2223) are arranged at positions of the sliding block corresponding to the third through holes (2224).

6. The polymer melt composite vibration injection molding device according to claim 4, characterized in that: The hydraulic cylinder (222) further comprises a piston rod (2222); the movable end of the piston rod (2222) is connected to the horizontal slide groove (2221).

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